Organic light emitting device

1. An organic light emitting device, comprising:

a first substrate;

scan lines and data lines arranged on the first substrate;

a plurality of unit pixels, wherein each unit pixel comprises a R sub-pixel corresponding to a red color, a G sub-pixel corresponding to a green color, and a B sub-pixel corresponding to a blue color positioned in a region on the first substrate defined by a crossing of the scan and data lines, wherein a number of the R, G, and B sub-pixels is different from one another, wherein each R, G and B sub-pixel comprises a first electrode, a second electrode, and a light-emitting layer interposed between the first and second electrodes, and wherein a number of the B sub-pixels that have a shortest life-time expectancy among the R, G and B sub-pixels is larger than a number of the R and G sub-pixels; and

a driver configured to apply a driving current to the B sub-pixels, which is different than a driving current applied to the R and G sub-pixels,

wherein a plurality of the B sub-pixels is driven by a same driving thin film transistor which is connected commonly to first electrodes of the B sub-pixels by conductive spacers,

wherein the driver is further configured to apply a driving current to each of the B sub-pixels that is less than the driving current applied to the R and G sub-pixels, and

wherein the plurality of the B sub-pixels are disposed adjacent to each other and on a same side of a corresponding scan line.

2. The device as claimed in claim 1 , wherein the R, G, and B sub-pixels have a same size.

3. The device as claimed in claim 1 , wherein a number of sub-pixels that have a lowest luminous efficiency among the R, G and B sub-pixels is larger than a number of the other sub-pixels.

4. The device as claimed in claim 1 , wherein a number of the R sub-pixels is larger than a number of the G sub-pixels, and

wherein a number of the B sub-pixels is larger than a number of the R sub-pixels.

5. The device as claimed in claim 1 , further comprising:

a second substrate having the driving thin film transistor formed thereon; and

conductive spacers electrically connecting the thin film transistors and the first electrodes,

wherein the first and second substrates are sealed together.

6. A method of fabricating an organic light emitting device, said method comprising:

forming scan lines and data lines on a first substrate;

forming a plurality of unit pixels, wherein each unit pixel comprises a R sub-pixel corresponding to a red color, a G sub-pixel corresponding to a green color, and a B sub-pixel corresponding to a blue color positioned in a region on the first substrate defined by a crossing of the scan and data lines, wherein a number of the R, G, and B sub-pixels is different from one another, and wherein each R, G and B sub-pixel comprises a first electrode, a second electrode and a light-emitting layer interposed between the first and second electrodes;

forming one driving thin film transistor on a second substrate;

electrically connecting the one driving thin film transistor with the B sub-pixels,

wherein a number of the B sub-pixels that have a shortest life-time expectancy among the R, G and B sub-pixels is larger than a number of the R and G sub-pixels; and

applying a driving current to the B sub-pixels, which is different than a driving current applied to the R and G sub-pixels,

wherein a plurality of the B sub-pixels is driven by the one driving thin film transistor which is connected commonly to first electrodes of the B sub-pixels by conductive spacers,

wherein the applying step applies the driving current to each of the B sub-pixels that is less than the driving current applied to the R and G sub-pixels, and

wherein the plurality of the B sub-pixels are disposed adjacent to each other and on a same side of a corresponding scan line.

7. The method as claimed in claim 6 , wherein the R, G, and B sub-pixels have a same size.

8. The method as claimed in claim 6 , wherein a number of sub-pixels that have a lowest luminous efficiency among the R, G and B sub-pixels is larger than a number of the other sub-pixels.

9. The method as claimed in claim 6 , wherein a number of the B sub-pixels is larger than a number of the R or G sub-pixels among the R, G and B sub-pixels.

10. The method as claimed in claim 6 , further comprising:

sealing the first and second substrates together.

11. The device as claimed in claim 1 , wherein the light-emitting layers of the R, G, and B sub-pixels are separated by buffer layers formed on the second electrode, and the first electrodes of the R, G, and B sub-pixels are separated by barrier ribs formed on the buffer layers, respectively.

12. The method as claimed in claim 6 , wherein the light-emitting layers of the R, G, and B sub-pixels are separated by buffer layers formed on the second electrode, and the first electrodes of the R, G, and B sub-pixels are separated by barrier ribs formed on the buffer layers, respectively.

13. The device as claimed in claim 1 , wherein the number of B sub-pixels in a single unit pixel is two and the number of R and G sub-pixels is one each.

14. The device as claimed in claim 13 , wherein the R, G and B-sub-pixels are disposed in a square shape with the two B sub-pixels being on a lower row and the R and G sub-pixels being on an upper row.

15. The method as claimed in claim 6 , wherein the number of B sub-pixels in a single unit pixel is three, the number of R sub-pixels is two and the number of G sub-pixels is one.

16. The method as claimed in claim 15 , wherein the R, G and B-sub-pixels are disposed in a rectangular shape with the three B sub-pixels being on a lower row, and the two R sub-pixels and the one G sub-pixel being on an upper row.

17. The device as claimed in claim 6 , wherein the number of B sub-pixels in a single unit pixel is three, the number of R sub-pixels is two and the number of G sub-pixels is one.

18. The device as claimed in claim 17 , wherein the R, G and B-sub-pixels are disposed in a rectangular shape with the three B sub-pixels being on a lower row, and the two R sub-pixels and the one G sub-pixel being on an upper row.